7981740 has 120 divisors (see below), whose sum is σ = 27036240. Its totient is φ = 1959552.

The previous prime is 7981717. The next prime is 7981783. The reversal of 7981740 is 471897.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an Ulam number.

It is a junction number, because it is equal to n+sod(n) for n = 7981695 and 7981704.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 20871 + ... + 21249.

It is an arithmetic number, because the mean of its divisors is an integer number (225302).

Almost surely, 2^7981740 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 7981740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13518120).

7981740 is an abundant number, since it is smaller than the sum of its proper divisors (19054500).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

7981740 is a wasteful number, since it uses less digits than its factorization.

7981740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 413 (or 402 counting only the distinct ones).

The product of its (nonzero) digits is 14112, while the sum is 36.

The square root of 7981740 is about 2825.1973382403. The cubic root of 7981740 is about 199.8477174128.

The spelling of 7981740 in words is "seven million, nine hundred eighty-one thousand, seven hundred forty".